Now, of course this is no problem if you're a truly manly man. You'll simply acknowledge the risk, but choose to ignore it, and insist that anybody who would evaluate risk when making decisions is "afraid of the water".
For many of the rest of us, here's an incident report that is seasonal and appropriate:
Seasonal warning: This little furball would love to sink your boat!
The sharp eye of a fellow club member was likely all that prevented the total loss of a substantial yacht at the Queen City Yacht Club moorage. Noting that the vessel's stern was well down in the water, the member discovering the problem phoned the boat owner at work and an immediate investigation began.
A muskrat had crawled up the exhaust pipe of the sinking yacht, and chewed through the rubber exhaust hose. This is not the first instance of muskrat damage to a boat, nor will it be the last. They naturally look for small holes in which to establish a nest, and the exhaust port of a boat looks very inviting. Underwater exhausts are especially vulnerable, but muskrats have no difficulty getting into exhausts within several inches of the surface as well. One into the exhaust system, a muskrat will either attempt to expand the size of the nest by digging and chewing in every direction and will also gnaw on everything available to trim down its constantly growing, rat-like teeth.
In cases where the exhaust hose is above the waterline and where a hole is not likely to flood the boat, the critters have been known to get out of the hose and into the bilge. That rubber hose connected to a through hull? It looks just like a big juicy root coming out of the ground- customary food for a muskrat. After a few minutes of nibbling with sharp teeth, the hose is breached and the bilge begins to flood.
Queen City Yacht Club keeps a 100 gallon per minute pump on hand at the marina. Some members rigged the pump to evacuate water from the sinking boat, and it took more than 20 minutes to drain the bilge. There were over 2,000 gallons of water aboard. That much water could easily sink a boat of more moderate size.
Reports are that the yacht's generator may have been damaged beyond repair. There are undoubtedly other problems as well. Worse yet, many yacht insurance policies *exclude* any damage caused by rodents or "varmints" so the unlucky victim of this incident may be out of pocket for some, or maybe all, of the repairs.
One of the club officers recommends stuffing a NERF football up the exhaust pipe this time of year. Local boatyards also offer stainless steel "grates" that can be permanently installed over the exhaust port, allowing free flow of the exhaust but keeping muskrats from crawling into the system.
If you see vegetation trailing from your exhaust pipe, you may already have muskrats aboard.